This invention samples and transmits the CEA-909 standard smart antenna analog pulse train waveforms using only a digital I/O pin for both mode A and mode B operation. This invention implements the smart antenna interface based on a single digital programmable counter. This counter is programmable so that it can tolerate or produce wide variation of symbol width.
This invention receives any hexadecimal or decimal format antenna programming code via a digital pin and generates a train of symbol sequence according to CEA-909 mode A operation standard. A programmable digital counter enables adjustment of the symbol width duration according to customer or antenna requirement.
This invention samples the incoming symbol for Mode B operation according to the CEA-909 standard through a digital input pin. This sampling uses the same digital counter as used in mode A operation. This counter is programmable to handle wide variation in incoming symbol width. After receiving the complete packet of symbols this interface translates it to hexadecimal format for easy user comprehension.
This invention is an all digital smart antenna interface. This invention uses only a digital input and an output pin. The same hardware is used for both Mode A antenna operation and Mode B antenna operation. Because this invention uses a single digital counter, it requires an insignificant digital chip area for the implementation. This invention requires only a few digital flip-flops and logic gates.